% Generated by roxygen2: do not edit by hand

% Please edit documentation in R/time-wise.R

\name{difference}

\alias{difference}

\title{Lagged differences}

\usage{

difference(x, lag = 1, differences = 1, default = NA, order_by = NULL)

}

\arguments{

\item{x}{A vector}

\item{lag}{A positive integer indicating which lag to use.}

\item{differences}{A positive integer indicating the order of the difference.}

\item{default}{The value used to pad \code{x} back to its original size after the

lag or lead has been applied. The default, \code{NULL}, pads with a missing

value. If supplied, this must be a vector with size 1, which will be cast

to the type of \code{x}.}

\item{order_by}{An optional secondary vector that defines the ordering to use

when applying the lag or lead to \code{x}. If supplied, this must be the same

size as \code{x}.}

}

\value{

A numeric vector of the same length as \code{x}.

}

\description{

\ifelse{html}{\href{https://lifecycle.r-lib.org/articles/stages.html#stable}{\figure{lifecycle-stable.svg}{options: alt='[Stable]'}}}{\strong{[Stable]}}

}

\examples{

# examples from base

difference(1:10, 2)

difference(1:10, 2, 2)

x <- cumsum(cumsum(1:10))

difference(x, lag = 2)

difference(x, differences = 2)

# Use order_by if data not already ordered (example from dplyr)

library(dplyr, warn.conflicts = FALSE)

tsbl <- tsibble(year = 2000:2005, value = (0:5)^2, index = year)

scrambled <- tsbl \%>\% slice(sample(nrow(tsbl)))

wrong <- mutate(scrambled, diff = difference(value))

arrange(wrong, year)

right <- mutate(scrambled, diff = difference(value, order_by = year))

arrange(right, year)

}

\seealso{

\link[dplyr:lead-lag]{dplyr::lead} and \link[dplyr:lead-lag]{dplyr::lag}

}